We first establish some new critical point theorems for nonlinear dynamical systems in cone metric spaces or usual metric spaces, and then we present some applications to generalizations of DancšHegedüs-Medvegyev’s principle and the existence theorem related with Ekeland’s variational principle, Caristi’s common fixed point theorem for multivalued maps, Takahashi’s nonconvex minimization theore...

We study common fixed point theorems for a finite family of discontinuous and noncommutative single-valued functions defined in complete metric spaces. We also study a common fixed point theorem for two multivalued self-mappings and a stationary point theorem in complete metric spaces. Throughout this paper, we establish common fixed point theorems without commuting and continuity assumptions. ...